If you are like many folks (myself included), you've got several cordless phones of varying vintage around the house. I don't know which one is doing it, but occasionally when the phone rings I lose my connection. Most of the 2.4 phones randomly pick a channel. If it is the one your router is set for, it will disrupt your network while you are on the phone. This isn't a problem often, and newer phones may not do this. I haven't gone through my phones to figure out which one it is, though. (I've got a siemens, two vtechs, a lucent, and a new uniden.) That being said, this is an only occasional problem and it sounds like it won't be a problem with newer routers (mine is a year old "g" one) and phones.
Hope this helps.
Art